<template>
  <div>
    <!-- 面包屑导航区域-->
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>参数列表</el-breadcrumb-item>
    </el-breadcrumb>
    <!-- 卡片视图区域-->
    <el-card>
      <!-- 警告区域-->
      <el-alert
          title="注意：只允许为第三级分类设置相关参数！"
          type="warning" :closable="false" show-icon>
      </el-alert>
      <!-- 选择商品分类区域-->
      <el-row class="cat_opt">
        <el-col>
          <span>选择商品分类：</span>
          <!-- 选择商品分类的级联选择框-->
          <el-cascader
              v-model="selectedCateKeys"
              :options="cateList"
              :props="cateProps"
              @change="handleChange"></el-cascader>
        </el-col>
      </el-row>
      <!-- tabs页签区域-->
      <el-tabs v-model="activeName" @tab-click="handleTabClick">
        <!-- 添加动态参数的面板-->
        <el-tab-pane label="动态参数" name="many">
          <!-- 添加参数按钮-->
          <el-button @click="addDialogVisible = true" :disabled="isBtnDisabled" type="primary" size="mini">添加参数</el-button>
          <!-- 动态参数表格-->
          <el-table :data="manyTableData" border stripe>
            <!-- 展开行-->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <!-- 循环渲染Tag标签-->
                <el-tag @close="handleClose(i,scope.row)" v-for="(item,i) in scope.row.attr_vals" :key="i" closable>
                  {{item}}
                </el-tag>
                <!-- 输入的文本框-->
                <el-input
                    class="input-new-tag"
                    v-if="scope.row.inputVisible"
                    v-model="scope.row.inputValue"
                    ref="saveTagInput"
                    size="small"
                    @keyup.enter.native="handleInputConfirm(scope.row)"
                    @blur="handleInputConfirm(scope.row)"
                >
                </el-input>
                <!-- 添加按钮-->
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>

              </template>
            </el-table-column>
            <!-- 索引列-->
            <el-table-column type="index" label="#"></el-table-column>
            <!-- 其他列-->
            <el-table-column label="参数名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button @click="showEditDialog(scope.row.attr_id)" type="primary" icon="el-icon-edit" size="mini">编辑</el-button>
                <el-button @click="removeParams(scope.row.attr_id)" type="danger" icon="el-icon-delete" size="mini">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
        <!-- 添加静态属性的面板-->
        <el-tab-pane label="静态属性" name="only">
          <!-- 添加参数按钮-->
          <el-button @click="addDialogVisible = true" :disabled="isBtnDisabled" type="primary" size="mini">添加属性</el-button>
          <!-- 静态属性表格-->
          <el-table :data="onlyTableData" border stripe>
            <!-- 展开行-->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <!-- 循环渲染Tag标签-->
                <el-tag @close="handleClose(i,scope.row)" v-for="(item,i) in scope.row.attr_vals" :key="i" closable>
                  {{item}}
                </el-tag>
                <!-- 输入的文本框-->
                <el-input
                    class="input-new-tag"
                    v-if="scope.row.inputVisible"
                    v-model="scope.row.inputValue"
                    ref="saveTagInput"
                    size="small"
                    @keyup.enter.native="handleInputConfirm(scope.row)"
                    @blur="handleInputConfirm(scope.row)"
                >
                </el-input>
                <!-- 添加按钮-->
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>

              </template>
            </el-table-column>
            <!-- 索引列-->
            <el-table-column type="index" label="#"></el-table-column>
            <!-- 其他列-->
            <el-table-column label="属性名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button @click="showEditDialog(scope.row.attr_id)" type="primary" icon="el-icon-edit" size="mini">编辑</el-button>
                <el-button @click="removeParams(scope.row.attr_id)" type="danger" icon="el-icon-delete" size="mini">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
      </el-tabs>
    </el-card>

    <!-- 添加参数的对话框-->
    <el-dialog
        :title="'添加' + titleText"
        :visible.sync="addDialogVisible"
        width="50%" @close="addDialogClosed">
      <!-- 添加参数的表单-->
      <el-form :model="addForm" :rules="addFormRules" ref="addFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="addForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="addDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="addParams">确 定</el-button>
      </span>
    </el-dialog>

    <!-- 修改参数的对话框-->
    <el-dialog
        :title="'修改' + titleText"
        :visible.sync="editDialogVisible"
        width="50%" @close="editDialogClosed">
      <!-- 添加参数的表单-->
      <el-form :model="editForm" :rules="editFormRules" ref="editFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="editForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="editDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="editParams">确 定</el-button>
      </span>
    </el-dialog>
  </div>
</template>

<script>
export default {
  name: "Params",
  data(){
    return{
      // 商品分类列表
      cateList:[],
      // 级联选择器的配置
      cateProps: {
        expandTrigger: 'hover',
        value:'cat_id',
        label:'cat_name',
        children:'children'
      },
      // 级联选择器的双向绑定
      selectedCateKeys:[],
      // 被激活的页签的名称
      activeName:'many',
      // 动态参数的数据
      manyTableData:[],
      // 静态属性的数据
      onlyTableData:[],
      // 控制添加对话框的显示与隐藏
      addDialogVisible: false,
      // 添加参数的表单数据对象
      addForm:{
        attr_name:''
      },
      // 添加表单的验证规则对象
      addFormRules:{
        attr_name:[
          {
            required: true,
            message: '请输入参数名称',
            trigger: 'blur'
          },
        ]
      },
      // 控制修改对话框的显示与隐藏
      editDialogVisible: false,
      // 编辑参数的表单数据对象
      editForm:{},
      // 修改表单的验证规则对象
      editFormRules:{
        attr_name:[
          {
            required: true,
            message: '请输入参数名称',
            trigger: 'blur'
          },
        ]},
    }
  },
  created() {
    this.getCateList()
  },
  methods:{
    // 获取所有的商品分类列表
    async getCateList(){
      const {data:res} = await this.$http.get('categories')
      if (res.meta.status !== 200){
        return this.$message.error('获取商品分类失败！')
      }
      this.cateList = res.data
      // console.log(this.cateList);
    },
    // 级联选择框选中触发的函数
    handleChange(){
      this.getParamsData()
    },
    // tab页签点击函数的处理函数
    handleTabClick(){
      this.getParamsData()
      console.log(this.activeName);
    },
    // 获取参数的列表数据
    async getParamsData(){
      // 证明选中的不是三级分类
      if (this.selectedCateKeys.length !== 3) {
        this.selectedCateKeys = []
        // 清空表格数据
        this.manyTableData = []
        this.onlyTableData = []
        return
      }
      // 证明选中的是三级分类
      // console.log(this.selectedCateKeys);
      // 根据所选分类的id和当前所处的面板，获取对应的参数
      const {data:res} = await this.$http.get(`categories/${this.cateId}/attributes`,{params: {sel: this.activeName}})
      if (res.meta.status !== 200){
        return this.$message.error('获取参数列表失败！')
      }
      // 如果没有tag，就返回个空数组
      res.data.forEach(item => {
        item.attr_vals = item.attr_vals ? item.attr_vals.split(' ') : []
        // 控制单个item的文本框的显示与隐藏
        item.inputVisible = false
        // 文本框中输入值
        item.inputValue = ''
      })
      console.log(res.data);
      if (this.activeName === 'many'){
        this.manyTableData = res.data
      }else{
        this.onlyTableData = res.data
      }
    },
    // 监听添加对话框的关闭事件
    addDialogClosed(){
      this.$refs.addFormRef.resetFields()
    },
    // 点击按钮，添加参数
    addParams(){
      this.$refs.addFormRef.validate(async valid => {
        if (!valid) return
        const {data:res} = await this.$http.post(`categories/${this.cateId}/attributes`,{
          attr_name: this.addForm.attr_name,
          attr_sel: this.activeName
        })
        if (res.meta.status !== 201){
          return this.$message.error('添加参数失败！')
        }
        this.$message.success('添加参数成功！')
        this.addDialogVisible = false
        this.getParamsData()
      })
    },
    // 点击按钮，展示修改对话框
    async showEditDialog(attr_id){
      // 查询当前参数信息
      const {data:res} = await this.$http.get(`categories/${this.cateId}/attributes/${attr_id}`,{
        params:{attr_sel:this.activeName}
      })
      if (res.meta.status !== 200){
        this.$message.error('获取参数信息失败！')
      }
      this.editForm = res.data
      this.editDialogVisible = true
    },
    // 监听编辑对话框的关闭事件
    editDialogClosed(){
      this.$refs.editFormRef.resetFields()
    },
    // 点击按钮，修改参数
    editParams(){
      this.$refs.editFormRef.validate(async valid=> {
        if (!valid) return
        const {data:res} = await this.$http.put(`categories/${this.cateId}/attributes/${this.editForm.attr_id}`,{
          attr_name: this.editForm.attr_name,
          attr_sel: this.activeName,
          attr_vals: this.editForm.attr_vals
        })
        if (res.meta.status !== 200){
          return this.$message.error('修改参数失败！')
        }
        this.$message.success('修改参数成功！')
        this.getParamsData()
        this.editDialogVisible = false
      })
    },
    // 根据id删除对应的参数项
    async removeParams(attr_id){
      const confirmResult = await this.$confirm('此操作将永久删除该参数, 是否继续?', '提示', {
        confirmButtonText: '确定',
        cancelButtonText: '取消',
        type: 'warning'
        // 捕获所有报错，并直接return，下行箭头函数省略了return
      }).catch(err => err)
      // 这时，如果用户确认删除，返回得字符串为confirm
      // 如果用户取消删除，返回的字符串为cancel
      if (confirmResult !== 'confirm') {
        return this.$message.info('已取消删除!')
      }
      // 调用接口，真正发起请求
      const {data:res} = await this.$http.delete(`categories/${this.cateId}/attributes/${attr_id}`)
      if (res.meta.status !== 200) {
        return this.$message.error('删除参数失败！')
      }
      this.$message.success('删除参数成功！')
      this.getParamsData()
    },
    // tag标签文本框失去焦点或按下回车触发函数
    async handleInputConfirm(row){
      if (row.inputValue.trim().length === 0){
        row.inputValue = ''
        row.inputVisible = false
        return
      }
      // 如果没有return，则证明输入的内容有效，需要做后续处理
      row.attr_vals.push(row.inputValue.trim())
      row.inputValue = ''
      row.inputVisible = false
      // 需要发起网络请求，保存这次操作
      this.saveAttrVals(row)
    },
    // 将对attr_vals的操作保存到数据库
    async saveAttrVals(row){
      // 这时候只是保存到前端，并没有入库，刷新后就没有了。因此需要发起网络请求，保存这次操作
      const {data:res} = await this.$http.put(`categories/${this.cateId}/attributes/${row.attr_id}`,{
        attr_name:row.attr_name,
        attr_sel:row.attr_sel,
        attr_vals:row.attr_vals.join(' ')
      })
      if (res.meta.status !== 200){
        return this.$message.error('修改参数项失败！')
      }
      this.$message.success('修改参数项成功！')
    },
    // tag按钮，点击后显示文本框
    showInput(row){
      row.inputVisible = true
      // 让文本框自动获得焦点
      // $nextTick方法的作用：当页面上的元素被重新渲染之后，才会执行回调函数中的代码
      this.$nextTick(_ => {
        this.$refs.saveTagInput.$refs.input.focus();
      });
    },
    // 删除对应的参数可选项
    handleClose(i,row){
      row.attr_vals.splice(i,1)
      this.saveAttrVals(row)
    }
  },
  computed:{
    // 按钮需被禁用为true
    isBtnDisabled(){
      if (this.selectedCateKeys.length !== 3){
        return true
      }
      return false
    },
    // 当前选中的三级分类的id
    cateId(){
      if (this.selectedCateKeys.length === 3){
        return this.selectedCateKeys[2]
      }
      return null
    },
    // 动态计算标题的文本
    titleText(){
      if (this.activeName === 'many'){
        return '动态参数'
      }
      return '静态属性'
    }
  }
}
</script>

<style lang="less" scoped>
.cat_opt{
  margin: 15px 0;
}
.el-tag{
  margin: 10px;
}
.input-new-tag{
  width: 120px;
}
</style>